Merge pull request #498 from OneSignal/update/ios_build_cocoapods_version

[Added] Documented CocoaPods 1.11.3 or newer requirement

Author: jkasten2

MIGRATION.md

@@ -1,7 +1,9 @@
 # OneSignal Unity SDK 2.x.x to 3.x.x Migration Guide
 
 ## Requirements
-This guide assumes you are upgrading from a 2.x.x version of the OneSignal Unity SDK to the 3.x.x version. Additionally please ensure you are using Unity 2018.4 or newer.
+This guide assumes you are upgrading from a 2.x.x version of the OneSignal Unity SDK to the 3.x.x version. Additionally please ensure you are using:
+* Unity 2018.4 or newer
+* For iOS builds: CocoaPods 1.11.3 or newer
 
 ## Adding 3.x.x to your project
 Follow one of the following sections based on your previous install method of the OneSignal SDK.

README.md

@@ -33,6 +33,7 @@ And via many additional platforms. [Check them all out](https://documentation.on
 - A [OneSignal Account](https://app.onesignal.com/signup) if you do not already have one
 - Your OneSignal App ID which you can find under **Settings > Keys & IDs**
 - Unity 2018.4 or newer
+- iOS Builds: CocoaPods 1.11.3 or newer
 - In order to test push notifications you will need
   - An Android 4.0.3 or newer device or emulator with "Google Play services" installed
   - An iOS 9 or newer device (iPhone, iPad, or iPod Touch)